State Route 45 is a north–south state highway in the northeastern portion of the U.S. state of Ohio. Its southern terminus is at the State Route 7/State Route 39 concurrency in Wellsville, and its northern terminus is at State Route 531 about three miles (4.8 km) west of Ashtabula.

State Route 7 (SR 7), formerly known as Inter-county Highway 7 until 1921 and State Highway 7 in 1922, is a north–south state highway in the southern and eastern portions of the U.S. state of Ohio. At about 336 miles (541 km) in length, it is the longest state route in Ohio. Its southern terminus is an interchange with U.S. Route 52 (US 52) just west of Chesapeake. Its northern terminus also serves as the eastern terminus of SR 531 in Conneaut. The path of SR 7 stays within five miles (8.0 km) of the Ohio River for the southern portion, with the river being visible from much of the route. The road also remains within 10 miles (16 km) of the Pennsylvania state line for the northern portion.